A young US suicide bomber from Florida who blew himself up at an army post in the northwest of Syria. Moner Mohammad Abu Salha, alias Abu Hurayra al-Amriki, was believed to be the first American national to carry out such an attack in Syria's more than three-year-old war. Estimates of the number of foreign fighters who have flooded into Syria in the past three years range from between 9,000 to 11,000.

New Video Purports to Show American Suicide Bomber Moner Mohammad Abusalha

Chilling video has emerged purporting to show the first American to carry out a suicide attack in Syria burning his U.S. passport and issuing threats against the West. It is unclear how many people died in the May attack in Syria's Idlib Province, which has experienced heavy fighting in the country's civil war. But the State Department has confirmed that it believes that young Floridian Moner Mohammad Abusalha was the American involved.

A new video posted on social media Monday — and has not been independently verified — purports to show Abusalha before the attack, ripping his passport to shreds before setting it alight. "You think you're safe where you are, in America or Britain,” he says. “You think you are safe, you are not safe."

Abusalha, who grew up in Florida and attended several colleges before dropping out and moving abroad, was one of a growing number of foreign fighters travelling to Syria to take up arms in the country’s bloody civil war.

Syrian militants had released another video purporting to show Abusalha last week, in which the smiling Floridian also known by his nom de guerre Abu Huraya al-Amriki speaks in broken Arabic about his eagerness to go to heaven. The latest video posted online Monday appears to show a bearded Abusalha ranting in English against the West, warning that it is “going to the dirt” and to prepare “to enter the hellfire of Allah.”